This invention relates to shingles having multiple blend drops of granules and to methods and apparatus for depositing multiple blend drops onto a moving substrate.
A common method for the manufacture of asphalt shingles is the production of a continuous strip of asphalt shingle material followed by a shingle cutting operation which cuts the material into individual shingles. In the production of asphalt strip material, a substrate such as an organic felt or a glass fiber mat is passed through a coater containing liquid asphalt to form a tacky asphalt coated strip. Subsequently, the hot asphalt strip is passed beneath one or more granule applicators which apply the protective surface granules to portions of the asphalt strip material. The granule coated sheet is cooled and subsequently cut into individual shingles.
Some shingles are laminated shingles, typically having an overlay sheet with tabs and cutouts extending horizontally across the shingle, and also having an underlay sheet adhered underneath the overlay, with portions of the underlay being exposed through the overlay cutouts. Different coloration of the granules between the overlay and the underlay gives the laminated shingle an aesthetically pleasing appearance when the shingles are placed on a roof. Trilaminate shingles are also known, the trilaminate shingles having an overlay, an underlay, and a middle sheet. Both the overlay and the middle sheet have cutouts. Portions of the middle sheet and underlay are exposed through the overlay cutouts.
In a continuous process for manufacturing laminated shingles and trilaminate shingles, the cooled granule coated sheet is slit longitudinally, separating the granule coated sheet into continuous overlay and underlay strips (and also a middle sheet strip for trilaminate shingles). These continuous strips are fed continuously on top of one another, and adhered to each other with a laminating adhesive to form a continuous laminated sheet. The continuous laminated sheet is then cut into individual laminated or trilaminate shingles.
It would be advantageous if there could be developed a trilaminate shingle having an improved aesthetically pleasing appearance when the shingle is applied with other similar shingles as a roof covering on a roof.
The above objects as well as other objects not specifically enumerated are achieved by a trilaminate shingle having a horizontal longitudinal orientation. The shingle includes an overlay sheet having series of tabs and cutouts extending horizontally across the shingle. The shingle also includes a middle sheet having a series of tabs and cutouts extending horizontally across the shingle. The middle sheet cutouts are narrower horizontally than the overlay cutouts. The shingle also includes an underlay sheet beneath the middle sheet. The middle sheet is laminated beneath the overlay so that portions of the middle sheet, including at least some of the middle sheet cutouts, are exposed through the overlay cutouts. The underlay is laminated beneath the middle sheet so that portions of the underlay are exposed through the middle sheet cutouts and through the overlay cutouts. The exposed portions of the underlay sheet are generally darker than the middle sheet.
According to this invention there is also provided a trilaminate shingle having a horizontal longitudinal orientation. The shingle includes an overlay sheet having series of tabs and cutouts extending horizontally across the shingle. The shingle also includes a middle sheet having a series of tabs and cutouts extending horizontally across the shingle, the middle sheet cutouts being narrower horizontally than the overlay cutouts. The shingle also includes an underlay sheet beneath the middle sheet. The middle sheet is laminated beneath the overlay so that portions of the middle sheet, including at least some of the middle sheet cutouts, are exposed through the overlay cutouts. The underlay is laminated beneath the middle sheet so that portions of the underlay are exposed through the middle sheet cutouts and through the overlay cutouts. The middle sheet cutouts have a horizontal width that is less than about 25 percent of the average width of the overlay cutouts of the shingle.
Various objects and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiments, when read in light of the accompanying drawings.